Protective device for electric switchboards



Feb. 8, 1927.

G. W. ASHLOCK. JR

PROTECTIVE DEVICE FOR ELECTRIC SWITCHBOARDS Filed June 25, 1925' ammo ton flshlock Jn George Was My Patented Feb. 8, 1927.

PATENT OFFICE.

GEORGE WASHINGTON ASHLOCK, JR., OF OAKLAND, CALIFORNIA.

PROTECTIVE DEVICE FOR ELECTRIC SWITCHBOARDS.

Application filed June 25, 1923. Serial No. 647,514.

My invention is a protective device for electric switch boards.

My invention is illustrated in the accompanying drawing which forms apart of this 6 specification and the appended claim.

Referring to the drawing:

Figure 1 is a sectional view of my invention and a switch board to which my invention is applied, taken on line 11 ofFigure 2.

Figure 2 is a front elevation of my invention.

Figure 3 is a detail sectional view of the .base, showing how the studs are mounted in the base.

15 In the drawing, 1 indicates a switch board,

' including a base 2 of insulation, and a knife switch 3 and a fuse 4 mounted on said base. An arm 5 is secured to a bar 6 of insulation which connects the swinging ends of 20 the switch blades 7. Studs 10 projecting forwardly from the base 1. extend through the base and screw into bars 11 secured to the back of the base. A front plate 12 is riveted on the forward ends of the studs 10- in front of theswitchboard. Braces 13 mounted on the lower studs 10 and resting against base 1. extend upwardly and forwardly against the plate 12, and the forward end of the upper studs- 10 extend through r the upper forward endsr of the braces. thus bracing the forward ends of the upper studs and providing a rigid mount for the plate 12. An operating'lever 15 is fulcrumed in front of plate 12 in a bearing 16 on the front of said plate. A link 17 extends through a vertical slot18 in plate 12 and connects the arm 5 and lever 15. 20 is provided in the plate12 in front of fuse being hinged at its upper' 'edge.

A lug 21 extending from the front of the door 20 A door 1 permit access to the fuse, the door.

at the upper edge thereof is engaged by a cam 22 on the lower end of lever 15 to hold the door 20 closed when the lever is in switch closing'position and the switch 3 is closed as shown in Fig. 1, thus preventing access to the fuse while the switch is closed. Upon pulling the upper end of the lever 15 outward. the switch 3, through link 17 and arm 5 is opened. and the cam 22 disengages the lug 21. The door 20 may then be opened for access to the fuse 4. the switch at this time ,being open. Upon swinging the lever inwardly and closing the switch the cam 22 engages the lug 21, if the door is open, and closes the door.

The plate 12 and lever 15 being mounted in front of the switch board and insulated therefrom by base 2 and bar 6, prevent one from touching the switch board and receiving an electric shock.

Having described my invention, I claim:

In combination with an electric switch board, a plate, means for supporting said plate spaced from the switch board. a memher extending forwardly of said plate, an operating lever pivoted in said member, said plate having an opening to provide access to the-switch board, a door hinged at its upper edge covering said opening. a lug attached to said door near its upper edge. a cam formed on the lower end of said lever and adaptedito engage said lug, and a link pivoted at one end to said lever, extending through said plate and having its other end operatively connected to an electric si vitch on said switch board. said link. lever. us: and cam coacting to prevent the opening of the door when the switch is closed.

In testimony whereof I afiix my signature.

GEORGE WASHINGTON ASHLOCK, Jr. 

